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PGC +69457 Gravitational lense (Einstein cross), 


PGC +69457 Gravitational lense (Einstein cross)

PGC +69457 Gravitational lense (Einstein cross)

Technical card

Resolution: 967x771

Dates:Oct. 1, 2015

Frames: 10x30" -20C bin 1x1

Integration: 0.1 hours

Darks: ~20

Bias: ~20

Avg. Moon age: 18.65 days

Avg. Moon phase: 83.90%

Temperature: 8.00 job: 798718

RA center: 22h 41' 33"

DEC center: +3° 18' 32"

Pixel scale: 2.123 arcsec/pixel

Orientation: 162.042 degrees

Field radius: 0.365

Locations: Home Observatory, Syke, Niedersachsen, Germany


This is my probably impossible mission to capture an image of the so-called Einstein Cross.

But, at least, I found the Galaxy which works as a gravitational lense of a much more distant quasar Quasar : QSO2237+0305

( below red marker. I carefully checked against the Simbad database)
RA : 22h40m30.3s DE : 03°21'31"

This Galaxy, PGC +69457, has a brightness magnitude of 14.5 and is some 400 million light years away .
The actual "Einstein Cross" from that Quasar would only shine as 17.5 magnitude four star constellation around the gravitational lense galaxy core.

If I could separate that quasar light at all, this would be light as old as 8 billion lightyears away !!!
( current estimates of the age of our Universe is 13.8 billion years )

Remark :

Is it possible at all ?

The 12" Dobson has a theoretical angular resolution of 0.32".
The lensed quasar light beams are 1.4" distant to the gravitational lens galaxy core.
So far, so good ..
But the biggest problem is the required focal length (FL) to resolve the Einstein cross
at a given CCD chip. ( Atik 383L CCD : KAF-8300 = 5.4 micrometer )

Thumb rule : FL = D (305 mm) x 5 x CCD Pixel (5.4 micron) = 8235 mm

Any attempt to use Barlow lenses to come from 1500 mm to 8000 mm FL will fail.
(Losing too much light and precise tracking at this FL would be almost impossible)



License: None (All rights reserved)

Sky plot

Sky plot


PGC +69457 Gravitational lense (Einstein cross),